Till sidans topp

Sidansvarig: Webbredaktion
Sidan uppdaterades: 2012-09-11 15:12

Tipsa en vän

Gene amplification in the… - Göteborgs universitet Till startsida
Till innehåll Läs mer om hur kakor används på gu.se

Gene amplification in the murine SEWA system.

Artikel i vetenskaplig tidskrift
Författare G Levan
F Ståhl
Yvonne Wettergren
Publicerad i Mutation research
Volym 276
Nummer/häfte 3
Sidor 285-90
ISSN 0027-5107
Publiceringsår 1992
Publicerad vid Institutionen för laboratoriemedicin, Avdelningen för biomedicinsk laboratorievetenskap
Sidor 285-90
Språk en
Länkar www.ncbi.nlm.nih.gov/entrez/query.f...
Ämnesord Animals, Drug Resistance, genetics, Gene Amplification, genetics, Genes, myc, genetics, Hybrid Cells, Mice, Plasmids, genetics, Restriction Mapping, Tumor Cells, Cultured
Ämneskategorier Genetik


Considerable work with DNA amplification has been carried out in the murine SEWA ascites tumor cell system. In SEWA cells there is 'spontaneous' amplification of the c-myc oncogene, and transitions between different cytogenetic expressions of gene amplification such as DM (double minutes), CM (C-bandless chromosomes) and HSR (homogeneously staining regions) of the amplified DNA have been recorded during serial in vivo transplantations. In SEWA cells it has also been shown that the c-myc-containing DM will he lost under in vitro conditions, but are rapidly recovered if the cells are reinjected into animals. Additional gene amplification has been superimposed on the c-myc amplification in SEWA cells by stepwise selection in vitro, leading to resistance to different drugs, such as methotrexate, actinomycin D, colcemid and vincristine. Cytogenetically, DNA amplification is multifaceted and, in addition to the structures mentioned, it may also take the form of CB (chromatin bodies), which have been shown to be the carriers of resistance genes in hybrids between multidrug-resistant SEWA cells and Chinese hamster CHO cells. In most instances, DM are noncentromeric and distributed by a 'hitch-hiking' mechanism at mitosis; in one colcemid-resistant SEWA line, however, we have shown that the DM carry active centromeres. The molecular mechanism behind DNA amplification appears to be complex. We have shown that in four independently derived multidrug-resistant SEWA sublines the amplicons resided on circular molecules which were about 2500 kb long and carried at least five genes, including the three mouse mdr genes. Within the circles the DNA was unrearranged compared to the organization of the DNA in sensitive cells.

Sidansvarig: Webbredaktion|Sidan uppdaterades: 2012-09-11

På Göteborgs universitet använder vi kakor (cookies) för att webbplatsen ska fungera på ett bra sätt för dig. Genom att surfa vidare godkänner du att vi använder kakor.  Vad är kakor?